Turbine

[Guardiano]

Hi forum members,

In the case of a back pressure turbine, the output depends on the delta P between the inlet pressure and the exhaust pressure.What factors determine the efficiency of the turbine particularly on the exhaust side? I am on a site where the steam demand on a turbine has increased but the power output is significantly the same.
Thanks.

Guardiano

 

[rmw]

Several factors at play here. Are you sure that the inlet and outlet conditions are the same? Same amount of superheat, same pressure, same back pressure? Lower supply pressure/superheat or higher back pressure will increase steam flow for the same amount of work.

Is the temperature of the exhaust steam the same as before or higher (I would expect higher based on what you said.)

If all the above is the same, then I would look for internal mechanical problems, blade wear, stationary parts (diaphrams), nozzles, blade tip seals, etc.

rmw

 

[stgrme]

Supplementing rmw's response, does the turbine have any intermediate extractions for process steam or feedwater heating. These extractions will also affect the power output.